[TowerTalk] wire antennas

The National Electrical Code specifies wire size for antennas (I realize the US
NEC does not
apply to ON land), though the concern in the NEC is mostly mechanical - i.e. it
will stay up,
not fall and give someone an RF burn or electrical shock.
The NEC recognizes 3 categories:
Receive only antenna up to 35 feet: #18 hard drawn copper or copper clad steel.
Antenna with under 150 feet long span: #14 "
Antenna over 150 feet: #12 "
While I have put antennas that don't meet these guidelines, they also tended to
break within
a few years.
>From the point of view of losses, even #24 would only take 5 or 10% off
efficiency for an 80m dipole. Legal limit power in a 50 ohm antenna would be
under 6 amps
which would require #18 to #20 in an extension cord, but a wire in free air has
less heat
problems than bundled or in conduit so somewhat smaller wire would still stay
cool enough.
Darrel AK6I
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